AOAC Official Method 982.35
Reference Materials¹
First Action 1982

A. Definitions

Reference material (RM)

Option 1: Material or substance, one or more of whose property values are sufficiently homogeneous and well established to be used for calibration of an apparatus, the assessment of a measurement method, or for assigning values to materials.

Note: A reference material may be in the form of a pure or mixed gas, liquid or solid. Examples are water for the calibration of viscometers, sapphire as a heat capacity calibrant in calorimetry, and solutions used for calibration in chemical analysis.²

Option 2: Material, sufficiently homogeneous and stable with respect to one or more specified properties, which has been established to be fit for its intended use in a measurement process.

Note 1 – RM is a generic term.

Note 2 – Properties can be quantitative or qualitative (i.e., identity of substances or species)

Note 3 – Uses can include the calibration of a measurement system, assessment of a measurement procedure, assigning values to other materials, and quality control.

Note 4 – An RM can only be used for a single purpose in a given measurement.³

Certified reference material (CRM)

Option 1: Reference material, accompanied by a certificate, one or more of whose property values are certified by a procedure which establishes traceability to an accurate realization of the unit in which the property values are expressed, and for which each certified value is accompanied by an uncertainty at a stated level of confidence.

Note 1 – The definition of a “reference material certificate” is given in 4.2. (ISO VIM 1993)

Note 2 – CRMs are generally prepared in batches for which the property values are determined within stated uncertainty limits by measurements on samples representative of the whole batch.

Note 3 – The certified properties of certified reference materials are sometimes conveniently and reliably realized when the material is incorporated into a specially fabricated device, e.g. a substance of known triple-point into a triple-point cell, a glass of known optical density into a transmission filter, spheres of uniform particle size mounted on a microscope slide. Such devices may also be considered as CRMs.

Note 4 – All CRMs lie within the definition of “measurement standards” or “etalons” given in the “International Vocabulary of basic and general terms in metrology (VIM).”

Note 5 – Some RMs and CRMs have properties which, because they cannot be correlated with an established chemical structure or for other reasons, cannot be determined by exactly defined physical and chemical measurement methods. Such materials include certain biological materials such as vaccines to which an International unit has been assigned by the World Health Organization.²

*This definition, including its notes, are taken from ISO Guide 30:1992.

Option 2: Reference material, characterized by a metrologically valid procedure for one or more specified properties, accompanied by a certificate that provides the value of the specified property, its associated uncertainty, and a statement of metrological traceability.

Note 1 – The concept of value includes qualitative attributes such as identity or sequence. Uncertainties for such attributes may be expressed as probabilities.

Note 2 – Metrologically valid procedures for the production and certification of reference materials are given in, among others, ISO Guide 34 and 35.

Note 3 – ISO Guide 31 gives guidance on the contents of certificates.³

B. General Information

Table 982.35 lists selected issuing organizations and shows source codes together with names and addresses of these organizations.

Organizations listed are only representative of those supplying RMs. No claim is made as to completeness of information supplied. Catalogs or literature describing RMs are available from individual organizations. Because inventories of RMs are continually changing, inquiries should be made of the organizations concerning current availability of specific RMs.

Table 982.35: Sources of reference materials- organizations and addresses

AACC
American Association of Cereal Chemists
Check Sample Service
3340 Pilot Knob Rd
St. Paul, MN 55121-2097, USA
E-mail: bsimdars@scisoc.org
Website: http://www.aaccnet.org
Phone: 651-454-7250
Fax: 651-454-0766

AOCS
American Oil Chemists' Society
Smalley Check Sample Program
2211 West Bradley Avenue
Champaign, IL 61821-1827, USA E-mail: technical@aocs.org
Website: http://www.aocs.org/tech
Phone: 217-359-2344
Fax: 217-351-8089

BAM
Federal Institute for Materials Research and Testing
Unter den Eichen 87
D-12200 Berlin, Germany
E-mail: info@bam.de
Website: http://www.bam.de
Phone: +49-30-81 04-0
Fax: +49-30-8 11 20 29

IRMM
Institute for Reference Materials and Measurements
Joint Research Centre, European Commission
Retieseweg 111, 2440
Geel, Belgium
Email: jrc-irmm-rm-sales@ec.europa.eu
Website: http://www.irmm.jrc.be
Phone: +32-14-571 705
Fax: +32-14-590 406

IAEA
International Atomic Energy Agency
Analytical Quality Control Services
Laboratory Seibersdorf
PO Box 100
Wagraer Strasse 5
A-1400 Vienna, Austria
E-mail: official.mail@iaea.org
Website: http://www.iaea.org
Phone: +431 2600-0
Fax: +431 2600-7

LGC Promochem
Laboratory of the Government Chemist
National Physical Laboratory
Office of Reference Materials
Queens Road
Teddington, Middlesex TW11 OLY, UK
E-mail: atcc@lgc.co.uk
Website: http://www.lgc.co.uk/ref.asp
Phone: 44 (0) 20 8943 8489
Fax: 44 (0) 20 8943 8405

NIES
National Institute for Environmental Studies
16-2, Onagava
Tsukuba-Shi, Ibaraki 305-8506, Japan
E-mail: www@nies.go.jp
Website: http://www.nies.go.jp/
Phone: +81-298-50-2422
Fax: +81-298-50-2572

NIST
National Institute of Standards and Technology
Standard Reference Materials Group
100 Bureau Drive, Stop 2322
Gaithersburg, MD 20899-2322, USA
E-mail: srminfo@nist.gov
Website: http://ts.nist.gov/ts/htdocs/230/232/232.htm
Phone: 301-975-6776
Fax: 301-948-3730

NRCC
National Research Council of Canada
Certified Reference Materials Program

Institute for Marine Biosciences
1411 Oxford St.
Halifax, NS, Canada B3H 3Z1
E-mail: crm.imb@nrc.ca
Website: http://imb-ibm.nrc-cnrc.gc.ca/crmp/
Phone: 902-426-8281
Fax: 902-426-5426

Institute for National Measurement Standards
1200 Montreal Road, Bldg M-36
Ottawa, ON, Canada K1A 0R6
Email: crm.inms@nrc-cnrc.gc.ca
Website: http://inms-ienm.nrc-cnrc.gc.ca/en/calserv/crm_e.php
Phone: 613-993-2359
Fax: 613-993-2451

USP
U.S. Pharmacopeial Convention, Inc.
USP-NF Reference Standards
12601 Twinbrook Parkway
Rockville, MD 20852, USA
E-mail: custsvc@usp.org
Website: http://www.usp.org
Phone: 301-881-0666
Fax: 301-816-8148

References:

1. Technical Division on Reference Materials-Minutes of Executive Committee Meeting, January 22, 2003, AOAC INTERNATIONAL, Gaithersburg, MD, USA
2. International Vocabulary of Basic and General Terms in Metrology, 2nd ed. BIPM/IEC/IFCC/ISO/IUPAC/IUPAP/OIML, International Organization for Standardization (ISO), 1993 (VIM)
3. Referrence Materials – General and Statistical Principles for Certification, ISO Guide 35, 3rd Ed., 2006, International Organization for Standardization (ISO), 1993 (REMCO)

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